The Research Of Design And Analysis About Digging Shovel Of Cassava Harvester

Cassava is also called manioc, it is one of the three major potato crops (cassava, potatoes,sweet potatoes) in the world, and mainly distribute in Tropical and subtropical areas. It hasbecome an important energy material in recent years. With the development of deepprocessing industry of cassava starch and energy alcohol, cassava industry has turned into aburgeoning economic industry. For the past few years, the cultivated area of cassava isenlarged rapidly. Compared with some other tuber crops, the cassava has a larger laborcapacity and time cost for a deeper growth. So, it is a necessary development tendency formechanization harvest.The harvest of cassava is mainly consists of two process, digging and sieving. The digging isthe second process after knifing the cassava stem. The working performance of digging shovelhas a remarkable influence for the harvest of cassava. The resistance of digging shovel takesup65%-75%of the total resistance. It is an important indicator to measure the advantageperformance of digging shovel by the high digging ratio and damaged ratio. The designanalysis of digging shovel and the digging theory in the cassava harvesting are studied in thispaper. The main research contents about digging shovel are as follows:1) By means of choosing the reasonable design scheme of digging shovel, the theory of soilcompression and destruction based on the force analysis of shovel surface is introduced in thepaper. Designed the performance parameter, built the indicator of measuring crashing soilproperty, and made a numeric computing analysis by using Matlab software.2) A mathematic model of multiple objective functions is built to measure the crashing soilproperty of digging shovel, and an optimization design is also given to the dip angle of twostages shovel surface and the height of first order shovel surface. In order to study moreconveniently, the conception of virtual shovel surface dip angle is proposed. The dip anglescombination and the height of first order shovel surface with a major property are acquired.3) On the basis of structure parameters of two stages shovel surface, the three-dimensionalentity is built and introduced into ANSYS analysis software. The static analysis is given to thetwo stages shovel surface, a digging shovel with a major property is obtained. 4) Through established the geometry motion relationship of linkage mechanism between thetractor and cassava harvester, the relationship between the enter angle of tractor linkage andthe penetrating angle of digging shovel is researched in the paper.5) The field experiment was given to the second order curved surface shovel which wasdesigned by optimization. The statistical results of major indexes, which can reflect theharvest effect, were acquired. The test results indicated that the second order curved shovelhas a stable ploughing depth and a better digging property. Each index can meet thetechnological requirement, and the broken soil ability was also improved.